How Do I Prevent Roundworm in Cats?

As loving cat parents, we do everything we can to give our kitties the best possible care. But even the most attentive guardians can sometimes face unexpected challenges. One common and concerning problem is the roundworm.
These pesky creatures can cause a range of health issues for your cat and even pose a risk to humans! That’s why you need to know the signs of trouble and how to keep your whole family safe.
In this guide, I’ll provide you with valuable information about roundworm prevention, including the importance of deworming, hygiene tips, and possible environmental changes you can make to reduce the risk.
Let's work together to keep our cats (and ourselves) safe from these unwanted pests!
What Are Roundworms?
Roundworms are intestinal parasites. More specifically, they are parasites that live within the intestines of an infected cat. They get their name because they are round, like long tubes like strands of spaghetti (though significantly smaller than the popular pasta).
Their presence isn’t the biggest concern, instead, it is what they do to survive. While living within the intestines, the parasites feed off the nutrients moving through the host cat’s digestive tract. As they do, they rob the cat of the nutrients they need to support their growth and overall well-being.
What Causes Roundworms in Cats?
The first step in preventing a roundworm infestation is understanding where your cat may pick up these unwanted pests. Here are the most common causes you should be aware of:
Ingesting Infected Prey
Arguably the most common, cats who hunt and kill prey run the risk of ingesting a bird, rodent, or insect currently carrying the roundworm larvae. While this is often associated with outdoor cats, even an indoor cat could face this challenge if they catch a critter that has found its way into the house.
If you have a cat who enjoys going outdoors, even those who only go out when on a leash, pay careful attention to what they may be in contact with. This could include prey they are hunting or even recently killed prey they come across during their adventures.
Contaminated Environments
Even if your cat doesn’t find/ingest a contaminated bird or animal, they may also pick up the parasites from a shared environment. An infected animal may leave behind infected feces or roundworm eggs on common surfaces like soil and grass.
Whether your cat is ingesting the feces directly or grooming themselves later, ingesting roundworm eggs they may have picked up in their fur, it can lead to a roundworm infestation.
Shared Resources in Multi-Cat Homes
Do you have multiple cats? If so, be warned – a single infestation in your home can quickly spread and become a more widespread problem. Much like your cat could pick up roundworm eggs or larvae through contaminated environments outdoors, the same can occur in the home, where they share resources like litter boxes, food bowls, and water dishes.
Of course, this cause requires one of your cats to pick up the parasite somewhere else first, bringing it into the home. But it still deserves mention as it will impact some of my prevention tips below.
Mother-to-Kitten Transmission
If you have an infected pregnant mother cat or one who has recently given birth, there is a good chance that they will pass the parasite to their kittens. The first risk arises when the kittens are still in utero. If the kitten avoids the parasite before birth, they can also become infected by nursing off an infected mother cat.
Symptoms to Watch Out For
Roundworms are not responsible for significant health problems in an otherwise healthy adult cat, making them difficult to spot. A minor infection may not result in any noticeable symptoms at all! However, an infestation can be serious and potentially life-threatening for a young kitten or senior cat.
The parasites can be passed from an infected cat to other pets in your home or even to humans. So, even if your cat isn’t bothered by the parasite, it could lead to a bigger problem. The earlier you spot signs of trouble, the sooner you can contact your vet to address the issue.
The most common signs of roundworm in cats include:
- Vomiting (you may even see white or light brown worms in your cat’s vomit)
- Nausea
- Loss of Appetite
- Abdominal discomfort
- Swollen or enlarged belly, also described as a potbellied appearance
- Weight loss
- Coughing from roundworms in the lungs
- Dull, lifeless coat
- Stunted growth in kittens
- Visible worms in your cat’s stool
What is the Prognosis for a Cat with Roundworms?
Luckily, treatment, when given early, is highly effective. The prognosis is good at this stage, even in higher-risk cats, like kittens and seniors. However, if the infection is allowed to progress, the chance of recovery begins to drop significantly.
After diagnosing that your cat is carrying the parasite, your veterinarian will recommend a deworming medication. These treatments are fairly inexpensive and aren’t associated with many side effects or complications, making them a safe option. After giving the treatment, your cat will pass the dead or dying roundworms in their stool.
It is important to note that these treatments don’t work on roundworm eggs or larvae. To ensure the infestation is completely cleared up, your cat will need two or three treatments, approximately 2 to 3 weeks apart.
Tips to Prevent Roundworms in Your Cat
The best approach for any potential health problem or parasite is always to prevent a problem from happening. Here are a few steps you can take to keep your cat parasite-free:
Keep Your Cat’s Litter Box Clean
As we mentioned, one of the most significant risks for passing roundworms from one carrier to the next is through feces. Therefore, your cats’ litter box is a potential hot spot. Even if you haven’t spotted any signs of trouble, you should prioritize keeping the box clean and free from waste.
If keeping up with cleaning your cat’s box regularly is a struggle due to a busy schedule or other limitations, there are many self-cleaning litterboxes that could help with the dirty chore.
Some highly-rated options include:
- Litter Robot 4 (the box I currently use for my cats)
- PetSafe ScoopFree SmartSpin Automatic Cat Litter Box
- Neakasa M1 Open-Top Self-Cleaning Cat Litter Box
- PetSafe ScoopFree Crystal Pro Self-Cleaning Litter Box
- PETKIT PuraMax 2 Self-Cleaning Cat Litter Box
Deep Clean Your Cat’s Box Regularly
In addition to scooping your cat’s box daily (or multiple times daily), you should plan to do a deep clean of the litter box at least once a month. This should be done with a disinfectant cleaner that will remove any parasites, bacteria, and other risks to your cat’s health. While there are many products to choose from, many experts, including veterinarians, animal shelters, and kennels use and trust REScue One-Step Disinfectant Cleaner.
Wash Your Hands After Litter Box Cleaning
Whether doing a routine scoop or a deep clean, always wash your hands with a disinfectant soap afterward. This will not only help to prevent you from passing the parasite to your other pets, it will also reduce the risk of cross-contamination to the human members of your family.
Keep Cats Supervised Outdoors
Do you have a cat that loves spending time outdoors? I am a massive supporter of the idea of leash and harness training a cat. Why? It allows them to be outside and tap into their naturally curious nature while still giving you the ability to keep them safe from harm, like cars, predators, and more. One such hazard you can help to reduce is roundworms.
When spending time outdoors with your cat, keep an eye on what they are getting into. For example, you can prevent your cat from eating contaminated prey or getting into contaminated feces by spotting it early and keeping them away. This won’t 100% prevent contamination (there is still the risk of a contaminated environment and picking up roundworm eggs), but careful supervision will significantly reduce the risk!
Do a Quick Clean When Coming Indoors
If you do spend time outdoors with your cat, a quick cleanup is necessary. Even if you avoid any potential prey or feces during your explorations, there is a chance that they could pick up roundworm eggs on their paws. When they are grooming, these eggs can be ingested and cause a full infestation.
The best way to avoid this is to do a quick cleanup when coming inside. We keep a package of Earth Rated Pet Wipes by the front door. After any time where they are paws on the ground outdoors, they get their paws, legs, stomach, etc. wiped clean to remove any potential concerns.
Keep Up with Annual Checkups
We’ve all heard people mention the importance of annual checkups with your cat’s veterinarian, but this is a good example of why these appointments are crucial. This gives the vet a chance to check for any signs of trouble, possibly catching illnesses or diseases early (giving your cat a better prognosis) – which includes checking for signs of a parasite infection.
During this appointment, the vet will also give you recommendations regarding preventative products. Many heartworm medications will also protect your cat against roundworms. If you're unsure whether your current product has your cat covered, don’t be afraid to ask!
Take Steps to Control Insects/Rodents in the Home
As mentioned, hunting and ingesting infected prey is one of the biggest causes of roundworms in cats. We discussed keeping your cat from getting into trouble when spending time outdoors, but you should also consider the risk of exposure indoors.
If you are currently faced with the presence of insects or rodents in your home, take that concern seriously. Contact an exterminator to help you get control over the situation before it potentially becomes a much bigger problem. Avoid using poisons, as they could also put your pets at risk!
Take steps moving forward to avoid attracting insects and rodents to your home. This includes sealing cracks or gaps around your home where these unwanted visitors can get in, thoroughly cleaning up any food spills or messes, storing all food in your pantry in airtight containers, and staying on top of emptying garbage cans.
Keep New Pets Separated Initially
Are you bringing a new cat into the home? Have you recently found a stray or lost cat you’re currently housing while trying to find their family or connect with a local rescue (or keep, no judgment here)?
There are several essential things to consider when introducing a new pet to the family. In addition to carefully introducing them to avoid arguments and setting up safe spaces to set everyone up for success, there is always the risk that your newest addition will introduce a disease or parasite to your “safe space.” The only way to know your new friend is healthy enough to meet the rest of the family is to get them in for a vet check. Until that point, keep them safely separated.
Final Thoughts: Roundworms in Cats
While roundworm infestations usually don’t pose a significant health risk for your cat, they can lead to complications for both at-risk cats and even the people in your home. But, with proactive measures, you can keep your family safe.
Remember that regular deworming, keeping your cat’s home environment clean, and minimizing contact with potentially infected animals are all key steps in preventing your cat from picking up the parasite. If you’re concerned about your cat’s risk, contact your veterinarian for diagnosis and treatment (if necessary).
By following the prevention tips above, you can ensure your cat lives a long, healthy, and parasite-free life.
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Britt Kascjak is a proud pet mom, sharing her heart (and her home) with her “pack” which includes her husband John, their 2 dogs – Lucifer and Willow – and their 3 cats – Pippen, Jinx, and Theia. She has been active in the animal rescue community for over 15 years, volunteering, fostering and advocating for organizations across Canada and the US. In her free time, she enjoys traveling around the country camping, hiking, and canoeing with her pets.
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